In vivo satellite cell activation via Myf5 and MyoD in regenerating mouse skeletal muscle

• Published in: Journal of cell science Vol. 112 ( Pt 17); no. 17; pp. 2895 - 2901
• Main Authors: Cooper, R N, Tajbakhsh, S, Mouly, V, Cossu, G, Buckingham, M, Butler-Browne, G S
• Format: Journal Article
• Language: English
• Published: England 01.09.1999
• Subjects: Animals; beta-Galactosidase - analysis; Biomarkers; Cadherins - analysis; Cell Division; Cobra Cardiotoxin Proteins - pharmacology; Cobra Cardiotoxin Proteins - toxicity; DNA-Binding Proteins; Gene Expression Regulation, Developmental; Genes, Reporter; Heterozygote; Mice; Mice, Mutant Strains; Muscle Proteins - biosynthesis; Muscle Proteins - genetics; Muscle Proteins - physiology; Muscle, Skeletal - cytology; Muscle, Skeletal - drug effects; Muscle, Skeletal - physiology; MyoD Protein - biosynthesis; MyoD Protein - genetics; MyoD Protein - physiology; Myogenic Regulatory Factor 5; Recombinant Fusion Proteins - analysis; Regeneration - drug effects; Trans-Activators
• ISSN: 0021-9533; 1477-9137
• DOI: 10.1242/jcs.112.17.2895

Regeneration of adult skeletal muscle is an asynchronous process requiring the activation, proliferation and fusion of satellite cells, to form new muscle fibres. This study was designed to determine the pattern of expression in vivo of the two myogenic regulatory factors, Myf5 and MyoD during this process. Cardiotoxin was used to induce regeneration in the gastrocnemius and soleus muscles of heterozygous Myf5-nlacZ mice, and the muscles were assayed for the presence of (beta)-galactosidase (Myf5) and MyoD. Adult satellite cells identified by M-cadherin labelling, when activated, initially express either MyoD or Myf5 or both myogenic factors. Subsequently all proliferating myoblasts express MyoD and part of the population is (beta)-galactosidase (Myf5) positive. Furthermore, we demonstrate that activated satellite cells, which express either Myf5 or MyoD, do not accumulate selectively on fast or slow muscle fibres.